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Magnetic Properties of Oxovanadium(IV) Complexes of Substituted N-(Hydroxylalkyl) Salicylideneimines

Description: A series of oxovanadium(IV) complexes of Schiff bases derived from substituted salicylaldehyde and aminoalcohols has been prepared and characterized. The Schiff bases coordinate through 0, N, and 0 as tridentate bivalent ligands. The primary purpose of the investigation is to describe the structure and bonding in these complexes. The subnormal magnetic properties of the complexes provide much information about both the structure and the bonding in the complexes.
Date: May 1972
Creator: Carey, Elbert Franklin
Partner: UNT Libraries

Magnetic Properties of Copper (II) Complexes of Schiff Bases

Description: The synthesis and characterization of two new Schiff base copper(II) complexes are reported. These are Cu(acac: 2-amino-l-phenylethanol) and Cu(acac:2-amino-l-butanol). The ligands, derived from acetylacetone and the appropriate aminoalcohol, are dibasic tridentates with 0,N,O donor atoms. The magnetic properties of the complexes were studied at several temperatures between 78 OK and 296 OK. The magnetic moment of Cu(acac:2-amino-l-phenylethanol) varied little with temperature, and that of Cu(acac:2-amino-lbutanol) increased as the temperature was lowered. This is in contrast to the magnetic moment of Cu(acac:ethanolamine), which decreases as the temperature decreases. Molecular weight data, infrared spectra, magnetic data, electronic spectra, and electron spin resonance spectra of both complexes are reported and discussed.
Date: August 1975
Creator: Jones, William James
Partner: UNT Libraries

Magnetic Properties of Metal(II) Schiff Base Complexes

Description: Ligands prepared from various combinations of aldehydes and ketones with the appropriate aminealcohol were complexed with cupric acetate monohydrate. The complexes with O,NO or N,N,O donor atoms were synthesized to study the influences of the ligand on molecular structure, spin-spin interaction, and on the value of the exchange integral. The magnetic data indicated that of the eight Cu(II) complexes discussed, two behaved differently from known analogous compounds. Cu (benzoylacetone :ethanolamine) was compared to Cu(acac:ethanolamine), and Cu(pyrr:oaminophenol) was compared to Cu(acac:o-aminophenol). Each pair of complexes was postulated to have the same molecular structure. The synthesis and characterization of Mn(pyrr:oaminophenol) 2H2 is also discussed. The following physical data were collected and discussed: elemental analysis, melting point, molecular weight, infrared spectra, electronic spectra, and magnetic susceptibility.
Date: May 1976
Creator: Hines, Mary Katherine
Partner: UNT Libraries

Membrane boenergetics of salt tolerant organisms. Progress report, June 1993--June 1995

Description: Substantial progress was made on describing the pathway of the transported proton in bacteriorhodopsin, and the thermodynamics of the proton transfers. The underlying principle of the transport was identified as the alternating access of the retinal Schiff base toward the two membrane surfaces, regulated by electrostatic interaction between the retinylidene nitrogen and its counterion. Consistent with a shared transport mechanism for both retinal proteins, bacteriorhodopsin was converted into a balorhodopsin-like chloride pump by replacing asp-85 with threonine. This region is thereby identified as the active site that determines ion specificity. Description of the metal ion-dependent kinetics of the ATP hydrolysis provided clues to the structure of active site in the halobacterial ATPase.
Date: June 1, 1996
Creator: Lanyi, J.K.
Partner: UNT Libraries Government Documents Department

Supercritical fluid reactions for coal processing. Quarterly progress report, April 1, 1996--June 30, 1996

Description: Exciting opportunities exist for the application of supercritical fluid (SCF) reactions for the pre-treatment of coal. Utilizing reactants which resemble the organic nitrogen containing components of coal, we propose to develop a method to tailor chemical reactions in supercritical fluid solvents for the specific application of coal denitrogenation. The tautomeric equilibrium of a Schiff base was chosen as the model system and was investigated in supercritical ethane and cosolvent modified supercritical ethane.
Date: November 1, 1996
Creator: Eckert, C.A.
Partner: UNT Libraries Government Documents Department

Supercritical fluid reactions for coal processing. Quarterly report, January 1, 1996--March 31, 1996

Description: Exciting opportunities exist for the application of supercritical fluid (SCF) reactions for the pre-treatment of coal. Utilizing reactants which resemble the organic nitrogen containing components of coal, we propose to develop a method to tailor chemical reactions in supercritical fluid solvents for the specific application of coal denitrogenation. The tautomeric equilibrium of a Schiff base was chosen as the model system and was investigated in supercritical ethane and cosolvent modified supercritical ethane.
Date: October 1, 1996
Creator: Eckert, C.A.
Partner: UNT Libraries Government Documents Department

Application of chemical modification and spin-labeling techniques to the study of energy conversion by bacteriorhodopsin

Description: Light generates a pH gradient and an electrical potential across the purple membrane of Halobacterium halobium. We are investigating the time-resolved changes in protonation of the side chains of specific amino-acid residues and the correlation of these changes with photon absorption and the ensuing photo-reaction cycle. We seek to determine the precise molecular description of the photocycle and of the time dependent steps in the uptake, translocation, and release of protons by the retinal proton catalyst in this membrane, bacteriorhodopsin (BR). 14 references, 3 figures, 1 table.
Date: March 1, 1983
Creator: Packer, L.; Quintanilha, A.T. & Mehlhorn, R.J.
Partner: UNT Libraries Government Documents Department